The overall aim of this core is to provide each investigator with basic histological services for light and electron microscopy. This will consist primarily of providing investigators with appropriate fixatives followed by production of paraffin, frozen and plastic sections of fixed specimens generated by the various projects. These sections will be stained, or treated with antibodies (immunohistochemistry) or dipped in photographic emulsion (radio-autography) as dictated by each project as per their experimental design. In addition, computerized morphometry of selected specimens will be provided.